Coal mine tunnel safety monitoring system and method based on laser ranging

Abstract

The invention relates to a coal mine tunnel safety monitoring system and method based on laser ranging. The coal mine tunnel safety monitoring system comprises a distance measurement system, a safety judgment system and an alarm system. The distance measuring system comprises a support, a laser distance measuring device, an X-axis rotation driving device and a Y-axis rotation driving device. The laser distance measuring device is used for measuring the distance between each distance measuring point on the inner wall of the roadway and the laser distance measuring device; the rotation center line of the laser ranging device rotating around the X axis is the X-axis center line, and the rotation center line of the laser ranging device rotating around the Y axis is the Y-axis center line. The X-axis center line, the Y-axis center line and the optical axis center line of the laser ranging device are always intersected at the same point; the safety judgment system is used for judging the safety state of the roadway according to the distance change between the same distance measurement point and the laser distance measurement device in two adjacent monitoring periods; and the alarm system is used for giving an alarm when the roadway is in an unsafe state.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mining, and in particular to a coal mine tunnel safety monitoring system and method based on laser ranging. Background Art

[0002] There are many safety hazards in the process of coal mining, among which the safety of coal mine tunnels is one of them. The safety of coal mine tunnels directly affects the ability of coal mining. Once there are safety hazards in coal mine tunnels, the consequences are unimaginable. Therefore, in the process of coal mining, it is necessary to monitor the safety of coal mine tunnels in real time. Some current monitoring equipment cannot accurately monitor the tunnels in real time.

[0003] The surface displacement of the tunnel is the most basic content of tunnel mine pressure monitoring, including roof subsidence, bottom bulge and single-wall displacement. According to the monitoring results, the relationship curve between displacement and displacement speed with excavation working face and time can be drawn to analyze the deformation law of tunnel surrounding rock, which is an important reference for evaluating the stability of tunnel surrounding rock and support effect. The traditional tunnel surface displacement monitoring methods mainly include steel tape monitoring method, measuring rod monitoring method, measuring gun monitoring method, convergence meter monitoring method, etc. The above monitoring methods are easy to measure, can meet the general measurement accuracy requirements, and are widely used.

[0004] However, the above-mentioned measurement methods are all contact measurement methods. The arrangement of monitoring points in tunnels with relatively soft coal rock is cumbersome. As the cross-section of the tunnel increases, the measurement error will also increase. Moreover, the effect of continuously monitoring and recording the displacement of the tunnel surface cannot be achieved, which results in low efficiency and high labor intensity.

[0005] Therefore, a new non-contact ranging method is urgently needed to enable rapid and accurate monitoring of tunnel surface displacement. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a coal mine tunnel safety monitoring system based on laser ranging, which can quickly and accurately detect the displacement / deformation of the coal mine tunnel surface, thereby monitoring the overall safety of the tunnel.

[0007] The second object of the present invention is to provide a coal mine tunnel safety monitoring method based on laser ranging.

[0008] The technical solution of the present invention to solve the above technical problems is:

[0009] A coal mine tunnel safety monitoring system based on laser ranging includes a ranging system, a safety judgment system and an alarm system, wherein:

[0010] The distance measuring system comprises a bracket arranged in a coal mine tunnel, a laser distance measuring device arranged on the bracket, an X-axis rotation driving device for driving the laser distance measuring device to rotate along the X-axis, and a Y-axis rotation driving device for driving the laser distance measuring device to rotate along the Y-axis, wherein the laser distance measuring device is used to measure the distance between each distance measuring point on the inner wall of the tunnel and the laser distance measuring device; the rotation center line of the laser distance measuring device rotating around the X-axis is the X-axis center line, the rotation center line of the laser distance measuring device rotating around the Y-axis is the Y-axis center line, and the X-axis center line, the Y-axis center line and the optical axis center line of the laser distance measuring device always intersect at the same point;

[0011] The safety judgment system is used to judge the safety status of the tunnel based on the change in distance between the same distance measuring point and the laser distance measuring device in two adjacent monitoring cycles;

[0012] The alarm system is used to issue a warning when the tunnel is in an unsafe state.

[0013] Preferably, the X-axis rotation drive device includes an X-axis support frame and an X-axis rotation motor arranged on the X-axis support frame, wherein the X-axis support frame is a U-shaped structure, and the X-axis support frame includes an X-axis support longitudinal plate and X-axis support transverse plates arranged on both sides of the X-axis support longitudinal plate; both sides of the shell of the laser ranging device are rotatably connected to the X-axis support transverse plates respectively; the X-axis rotation motor is installed on the X-axis support transverse plate on one side and is connected to the shell of the laser ranging device; the rotation plane of the center line of the optical axis of the laser ranging device passes through the center of the X-axis support longitudinal plate.

[0014] Preferably, the Y-axis rotation drive device includes a Y-axis support frame and a Y-axis rotation motor arranged on the Y-axis support frame, wherein the center rotation of the X-axis support longitudinal plate is connected to the Y-axis support frame and connected to the main shaft of the Y-axis rotation motor.

[0015] Preferably, it also includes a lifting device for driving the laser ranging device to lift vertically, the lifting device includes a vertically arranged fixed frame, a lifting frame installed on the fixed frame, and a lifting drive mechanism for driving the lifting frame to move vertically, wherein the bracket is installed on the lifting frame; the lifting frame is slidably connected to the fixed frame; the lifting drive mechanism includes a lifting rack, a lifting gear, and a lifting motor for driving the lifting gear to rotate, wherein the lifting rack is installed on the fixed frame, the lifting gear is rotatably connected to the lifting frame, and the lifting motor is installed on the lifting frame and connected to the lifting gear.

[0016] Preferably, the lifting device also includes a lifting control mechanism for controlling the operation of the lifting drive mechanism, and the lifting control mechanism includes a detection sensor and a controller arranged on the bracket, wherein the detection sensors are divided into two groups, the two groups of detection sensors are arranged at 180 degrees, and the detection ends of the two groups of detection sensors are facing oppositely; when one group of detection sensors detects that there is an object in the lane that is about to pass through the bottom of the laser ranging device, the detection sensor sends a detection signal to the controller, and the controller controls the lifting drive mechanism to drive the laser ranging device to rise to avoid the object.

[0017] Preferably, it also includes a Z-axis rotation drive device for driving the laser ranging device to rotate around the Z-axis, and the Z-axis rotation drive device includes a Z-axis rotation motor arranged on the lifting frame, and the main shaft of the Z-axis rotation motor is connected to the bracket.

[0018] Preferably, it also includes an X-axis translation device for driving the fixed frame to move along the X-axis direction, the X-axis translation device includes a mobile frame arranged on the top of the fixed frame, a mobile guide rail arranged on the top surface of the tunnel, and an X-axis translation mechanism for driving the mobile frame to move on the mobile guide rail, wherein a translation rack is arranged at the bottom of the mobile guide rail, and the translation rack extends along the length direction of the mobile guide rail; the mobile frame is installed on the mobile guide rail through a sliding structure, and the mobile frame is provided with a translation gear at a position corresponding to the translation rack, and the translation gear is meshed with the translation rack; the X-axis translation mechanism is used to drive the translation gear to rotate.

[0019] Preferably, there are two groups of translation racks, which are arranged in parallel. Correspondingly, there are two groups of translation gears, which are arranged in parallel, and each group of translation gears includes two translation gears. The two translation gears are connected by a rotating shaft and are respectively meshed with the two groups of translation racks.

[0020] Preferably, the sliding structure includes a guide wheel group arranged on the mobile frame and located on both sides of the mobile guide rail, and the mobile guide rail is provided with a guide groove cooperating with the guide wheel group, and the guide groove extends along the length direction of the mobile guide rail; each guide group includes guide wheels arranged in parallel and rotatably connected to the mobile frame.

[0021] A coal mine tunnel safety monitoring method based on laser ranging includes the following steps:

[0022] Step S1: start the laser distance measuring device;

[0023] Step S2: the X-axis rotation drive device drives the laser distance measuring device to rotate around the X-axis, and at the same time records the distance data between each distance measuring point on the inner wall of the lane detected by the laser distance measuring device and the laser distance measuring device;

[0024] Step S3: the Y-axis rotation drive device drives the X-axis rotation drive device and the laser distance measuring device to rotate around the Y-axis by a predetermined angle; then step S2 is repeated; until the distance data between all the distance measuring points on the inner wall of the lane and the laser distance measuring device are detected;

[0025] Step S4: Enter the next monitoring cycle, repeat steps S2 and S3, and complete the distance data between each distance measuring point on the inner wall of the lane and the laser distance measuring device in the next monitoring cycle;

[0026] Step S5: Repeat step S4 to obtain the distance data between each distance measuring point on the inner wall of the tunnel and the laser distance measuring device in multiple monitoring cycles, and determine the safety status of the tunnel by measuring the change in the distance between the same distance measuring point and the laser distance measuring device in two or more adjacent monitoring cycles and judging whether the change value is within the allowable range;

[0027] Step S6: When the tunnel is in a safe state, the coal mine tunnel safety monitoring system continues to monitor; when it is in an unsafe state, the alarm system in the coal mine tunnel safety monitoring system issues an alarm prompt.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The ranging system in the coal mine tunnel safety monitoring system based on laser ranging of the present invention drives the laser ranging device to rotate along the X-axis through the X-axis rotation driving device, so as to achieve ranging of multiple positions (i.e., ranging points) on a plane in the tunnel, and then drives the laser ranging device to rotate a predetermined angle through the Y-axis rotation driving device, and then drives the laser ranging device to rotate along the X-axis through the X-axis rotation driving device, so as to achieve ranging of multiple positions (i.e., ranging points) on another plane in the tunnel. Repeat the above operation to achieve ranging of multiple positions (i.e., ranging points) in the tunnel, so as to obtain the distance data of the laser ranging device to each ranging point on the inner wall of the tunnel, and monitor according to a preset time period to obtain the distance data between each ranging point on the inner wall of the tunnel and the laser ranging device in multiple monitoring periods, and judge whether the distance change value is within the allowable range by comparing the distance change between the same ranging point and the laser ranging device in two or more adjacent monitoring periods, so as to achieve the judgment of the safety of the tunnel, thereby timely discovering the potential safety hazards of the tunnel, and thus ensuring the life safety of the construction personnel.

[0030] 2. The X-axis center line, Y-axis center line and optical axis center line of the laser ranging device in the coal mine tunnel safety monitoring system based on laser ranging of the present invention always intersect at the same point; thus, it can be ensured that when the laser ranging device scans and measures the distance of the inner wall surface of the tunnel, its reference point is the same, that is, the intersection point; thus, within the same monitoring cycle, the distance data between each ranging point at different monitoring planes and the laser ranging device can be directly applied without the need for mathematical transformation, thereby reducing the difficulty of calculation and greatly improving the monitoring efficiency.

[0031] 3. The coal mine tunnel safety monitoring system based on laser ranging of the present invention drives the laser ranging device to rotate around the X-axis and the Y-axis through the X-axis rotation drive device and the Y-axis rotation drive device, so that the inner wall of the entire tunnel can be scanned and detected without changing the position of the coal mine tunnel safety monitoring system based on laser ranging of the present invention, and the monitoring efficiency is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The figure is a schematic diagram of the installation of the coal mine tunnel safety monitoring system based on laser ranging of the present invention.

[0033] Figure 2 This is the installation front view of the coal mine tunnel safety monitoring system based on laser ranging of the present invention.

[0034] Figure 3 This is a schematic diagram of the installation of the coal mine tunnel safety monitoring system based on laser ranging of the present invention (excluding the tunnel).

[0035] Figure 4 and Figure 5 The schematic diagrams are structural diagrams of the coal mine tunnel safety monitoring system based on laser ranging from two different perspectives of the present invention.

[0036] Figure 6 It is a structural schematic diagram of the X-axis translation device.

[0037] Figure 7 It is a structural schematic diagram of the lifting device.

[0038] Figure 8 It is a schematic diagram of the structures of the X-axis rotation drive device, the Y-axis rotation drive device and the Z-axis rotation drive device. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0040] See also Figure 1-Figure 8 The coal mine tunnel safety monitoring system based on laser ranging of the present invention includes a ranging system, a safety judgment system and an alarm system, wherein:

[0041] The distance measuring system comprises a bracket 5 arranged in a coal mine tunnel 1, a laser distance measuring device 2 arranged on the bracket 5, an X-axis rotation driving device for driving the laser distance measuring device 2 to rotate along the X-axis, and a Y-axis rotation driving device for driving the laser distance measuring device 2 to rotate along the Y-axis, wherein the rotation center line of the laser distance measuring device 2 rotating around the X-axis is the X-axis center line, the rotation center line of the laser distance measuring device 2 rotating around the Y-axis is the Y-axis center line, the X-axis center line, the Y-axis center line and the optical axis center line 11 of the laser distance measuring device 2 always intersect at the same point; in this way, it can be ensured that the laser distance measuring device 2 can detect the tunnel 1 When the inner wall surface is scanned and measured, the reference points are the same, that is, the intersection of the X-axis center line, the Y-axis center line and the optical axis center line 11. In this way, within the same monitoring cycle, the distance data between each distance measuring point at different monitoring planes and the laser distance measuring device 2 can be directly applied without the need for mathematical transformation, thereby reducing the difficulty of calculation and greatly improving the monitoring efficiency. For example, when three-dimensional modeling of the tunnel is performed after collecting distance data, the distance data between each distance measuring point at different monitoring planes and the laser distance measuring device 2 (as well as the position of the distance measuring point) do not need to be transformed in coordinates, that is, they can be directly applied, which can reduce the difficulty of modeling and improve modeling efficiency.

[0042] The safety judgment system is used to judge the safety status of the tunnel 1 based on the change in distance between the same distance measurement point and the laser distance measurement device 2 in two adjacent monitoring cycles;

[0043] The alarm system is used to issue a warning, such as an alarm sound, when the tunnel 1 is in an unsafe state.

[0044] See also Figure 1-Figure 8 The X-axis rotation drive device includes an X-axis support frame 9 and an X-axis rotation motor 10 arranged on the X-axis support frame 9, wherein the X-axis support frame 9 is a U-shaped structure, and the X-axis support frame 9 includes an X-axis support longitudinal plate and an X-axis support transverse plate arranged on both sides of the X-axis support longitudinal plate; the two sides of the shell of the laser ranging device 2 are respectively rotatably connected to the X-axis support transverse plate; the X-axis rotation motor 10 is installed on the X-axis support transverse plate on one side, and the main shaft is connected to the shell of the laser ranging device 2; the rotation plane of the optical axis center line 11 of the laser ranging device 2 passes through the center of the X-axis support longitudinal plate.

[0045] See also Figure 1-Figure 8The Y-axis rotation drive device includes a Y-axis support frame 8 and a Y-axis rotation motor 7 arranged on the Y-axis support frame 8, wherein the center rotation of the X-axis support longitudinal plate is connected to the Y-axis support frame 8 and is connected to the main shaft of the Y-axis rotation motor 7; the X-axis support longitudinal plate is driven to rotate around its center by the Y-axis rotation motor 7, and since the rotation plane of the optical axis center line of the laser ranging device 2 passes through the center of the X-axis support longitudinal plate, it can be ensured that the X-axis center line, the Y-axis center line and the optical axis center line 11 of the laser ranging device 2 always intersect at the same point.

[0046] See also Figure 1-Figure 8 The coal mine tunnel safety monitoring system based on laser ranging of the present invention also includes a lifting device 3 for driving the laser ranging device 2 to vertically lift and lower, the lifting device 3 includes a vertically arranged fixed frame 301, a lifting frame installed on the fixed frame 301, and a lifting drive mechanism for driving the lifting frame to vertically move, wherein the bracket 5 is installed on the lifting frame; the lifting frame is slidably connected to the fixed frame 301; the lifting drive mechanism includes a lifting rack 302, a lifting gear 303, and a lifting motor 304 for driving the lifting gear 303 to rotate, wherein the lifting rack 302 is installed on the fixed frame 301, the lifting gear 303 is rotatably connected to the lifting frame, the lifting motor 304 is installed on the lifting frame and connected to the lifting gear 303, and is used to drive the lifting gear 303 to rotate, thereby driving the lifting frame (and the X-axis rotation drive device, the Y-axis rotation drive device and the Z-axis rotation drive device connected to the lifting frame) to rise or fall;

[0047] In order to realize the control of the lifting drive mechanism, the lifting device 3 also includes a lifting control mechanism for controlling the operation of the lifting drive mechanism, and the lifting control mechanism includes a detection sensor 6 and a controller arranged on the bracket 5, wherein the detection sensor 6 is divided into two groups, and the two groups of detection sensors 6 are arranged at 180 degrees, and the detection ends of the two groups of detection sensors 6 are facing oppositely; when one group of detection sensors 6 detects that there is a moving object in the lane 1 and is about to pass through the bottom of the laser ranging device 2, the detection sensor 6 sends a detection signal to the controller, and the controller controls the lifting drive mechanism to drive the laser ranging device 2 to rise to avoid the object.

[0048] See also Figure 1-Figure 8The coal mine tunnel safety monitoring system based on laser ranging of the present invention also includes a Z-axis rotation drive device for driving the laser ranging device 2 to rotate around the Z-axis. The Z-axis rotation drive device includes a Z-axis rotation motor 11 arranged on the lifting frame. The main shaft of the Z-axis rotation motor 11 is connected to the bracket 5, and is used to drive the laser ranging device 2 to rotate around the main shaft of the Z-axis rotation motor 11. In this way, the bracket 5 and the laser ranging device 2, the X-axis rotation drive device and the Y-axis rotation drive device on the bracket 5 can be rotated to the other side of the lifting frame, that is, it can be moved from the right side of the lifting frame. The work is transferred to the left side of the lifting frame, so that the interference of the lifting frame (and the fixed frame 301) during detection can be avoided. It is equivalent to saying that, with the vertical plane where the lifting frame is located as the dividing line, when the bracket 5 and the laser ranging device 2, the X-axis rotation drive device and the Y-axis rotation drive device on the bracket 5 are located on the left side, the area to the left of the vertical plane is scanned and measured; when the bracket 5 and the laser ranging device 2, the X-axis rotation drive device and the Y-axis rotation drive device on the bracket 5 are located on the right side, the area to the right of the vertical plane is scanned and measured; this can further improve the detection accuracy.

[0049] See also Figure 1-Figure 8 The coal mine tunnel safety monitoring system based on laser ranging of the present invention also includes an X-axis translation device 401 for driving the fixed frame 301 to move along the X-axis direction, and the X-axis translation device 401 includes a mobile frame 401 arranged on the top of the fixed frame 301, a mobile guide rail arranged on the top surface of the tunnel 1, and an X-axis translation mechanism for driving the mobile frame 401 to move on the mobile guide rail, wherein a translation rack is arranged at the bottom of the mobile guide rail, and the translation rack extends along the length direction of the mobile guide rail; The frame 401 is installed on the moving guide rail through a sliding structure. The moving frame 401 is provided with a translation gear 403 at a position corresponding to the translation rack, and the translation gear 403 is meshed with the translation rack; the X-axis translation mechanism is used to drive the translation gear 403 to rotate. The X-axis translation mechanism is an X-axis motor 404, which drives the translation gear 403 to rotate through the X-axis motor 404, thereby driving the laser ranging device 2 to move horizontally, so as to cooperate with the lifting device 3 to avoid moving objects in the tunnel 1, such as construction robots or construction personnel.

[0050] In this embodiment, there are two groups of translation racks, which are arranged in parallel. Correspondingly, there are two groups of translation gears 403, which are arranged in parallel, and each group of translation gears 403 includes two translation gears 403, which are connected by a rotating shaft and meshed with the two groups of translation racks respectively; the sliding structure includes a group of guide wheels 402 arranged on the moving frame 401 and located on both sides of the moving guide rail, and the moving guide rail is provided with a guide groove that cooperates with the guide wheel group 402, and the guide groove extends along the length direction of the moving guide rail; each group of guide wheels 402 includes guide wheels that are arranged in parallel and are rotatably connected to the moving frame 401; by setting the sliding structure, not only can the movement of the moving frame 401 be guided, but also the two groups of guide wheels 402 are located on both sides of the moving guide rail, which can limit the moving frame 401, thereby preventing the moving frame 401 from falling off the moving guide rail.

[0051] See also Figure 1-Figure 8 The coal mine tunnel safety monitoring method based on laser ranging of the present invention comprises the following steps:

[0052] Step S1: start the laser distance measuring device 2;

[0053] Step S2: the X-axis rotation driving device drives the laser distance measuring device 2 to rotate around the X-axis, and at the same time records the distance data between each distance measuring point on the inner wall of the tunnel 1 detected by the laser distance measuring device 2 and the laser distance measuring device 2;

[0054] Step S3: the Y-axis rotation drive device drives the X-axis rotation drive device and the laser distance measuring device 2 to rotate around the Y-axis by a predetermined angle; then step S2 is repeated; until the distance data between all the distance measuring points on the inner wall of the lane 1 and the laser distance measuring device 2 are detected;

[0055] Step S4: Enter the next monitoring cycle, repeat steps S2 and S3, and complete the distance data between each distance measuring point on the inner wall of the lane 1 and the laser distance measuring device 2 in the next monitoring cycle;

[0056] Step S5: Repeat step S4 to obtain the distance data between each ranging point on the inner wall of the tunnel 1 and the laser ranging device 2 within multiple monitoring cycles, and judge the safety status of the tunnel 1 by measuring the change (i.e., difference) of the distance between the same ranging point and the laser ranging device 2 within two or more adjacent monitoring cycles, and judging whether the change value is within the allowable range; if it is within the allowable range, it can be determined that the tunnel 1 is currently safe; if it exceeds the allowable range, and the proportion of the ranging points exceeding the allowable range to all the ranging points does not reach the warning value, it can enter the alert state; when the proportion of the ranging points exceeding the allowable range to all the ranging points reaches the warning value, it is determined that the tunnel 1 is unsafe, and the alarm system immediately sounds an alarm to remind personnel to stop working and evacuate.

[0057] In addition to the above method, a three-dimensional model of the tunnel 1 can also be constructed based on the distance data from each ranging point to the laser ranging device 2 collected in each monitoring cycle; wherein, the position of the ranging point in each monitoring cycle can be the same or different, and the distance data from the ranging point to the laser ranging device 2 in multiple monitoring cycles can be used to obtain the position coordinates of each ranging point, and use this to build a three-dimensional model of the tunnel 1, and then judge whether the distance change value between the ranging point in the three-dimensional model and the laser ranging device 2 is within the allowable range to judge the safety of the tunnel 1.

[0058] The above is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited to the above content. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A coal mine tunnel safety monitoring system based on laser ranging, characterized in that: It includes distance measurement system, safety judgment system and alarm system, among which: The distance measuring system comprises a bracket arranged in a coal mine tunnel, a laser distance measuring device arranged on the bracket, an X-axis rotation driving device for driving the laser distance measuring device to rotate along the X-axis, and a Y-axis rotation driving device for driving the laser distance measuring device to rotate along the Y-axis, wherein the laser distance measuring device is used to measure the distance between each distance measuring point on the inner wall of the tunnel and the laser distance measuring device; the rotation center line of the laser distance measuring device rotating around the X-axis is the X-axis center line, the rotation center line of the laser distance measuring device rotating around the Y-axis is the Y-axis center line, and the X-axis center line, the Y-axis center line and the optical axis center line of the laser distance measuring device always intersect at the same point; The safety judgment system is used to judge the safety status of the tunnel based on the change in distance between the same distance measurement point and the laser distance measurement device in multiple adjacent monitoring cycles; The alarm system is used to issue a warning when the tunnel is in an unsafe state.

2. The coal mine tunnel safety monitoring system based on laser ranging according to claim 1 is characterized in that: The X-axis rotation drive device includes an X-axis support frame and an X-axis rotation motor arranged on the X-axis support frame, wherein the X-axis support frame is a U-shaped structure, and the X-axis support frame includes an X-axis support longitudinal plate and an X-axis support transverse plate arranged on both sides of the X-axis support longitudinal plate; the two sides of the shell of the laser ranging device are respectively rotatably connected to the X-axis support transverse plate; the X-axis rotation motor is installed on the X-axis support transverse plate on one side and is connected to the shell of the laser ranging device; the rotation plane of the center line of the optical axis of the laser ranging device passes through the center of the X-axis support longitudinal plate.

3. The coal mine tunnel safety monitoring system based on laser ranging according to claim 2 is characterized in that: The Y-axis rotation drive device includes a Y-axis support frame and a Y-axis rotation motor arranged on the Y-axis support frame, wherein the center rotation of the X-axis support longitudinal plate is connected to the Y-axis support frame and is connected to the main shaft of the Y-axis rotation motor.

4. The coal mine tunnel safety monitoring system based on laser ranging according to claim 3 is characterized in that: It also includes a lifting device for driving the laser ranging device to lift vertically, the lifting device includes a vertically arranged fixed frame, a lifting frame installed on the fixed frame, and a lifting drive mechanism for driving the lifting frame to move vertically, wherein the bracket is installed on the lifting frame; the lifting frame is slidably connected to the fixed frame; the lifting drive mechanism includes a lifting rack, a lifting gear, and a lifting motor for driving the lifting gear to rotate, wherein the lifting rack is installed on the fixed frame, the lifting gear is rotatably connected to the lifting frame, and the lifting motor is installed on the lifting frame and connected to the lifting gear.

5. The coal mine tunnel safety monitoring system based on laser ranging according to claim 4 is characterized in that: The lifting device also includes a lifting control mechanism for controlling the operation of the lifting drive mechanism, and the lifting control mechanism includes a detection sensor and a controller arranged on the bracket, wherein the detection sensors are divided into two groups, the two groups of detection sensors are arranged at 180 degrees, and the detection ends of the two groups of detection sensors face opposite directions; when one group of detection sensors detects that an object in the lane is about to pass through the bottom of the laser ranging device, the detection sensor sends a detection signal to the controller, and the controller controls the lifting drive mechanism to drive the laser ranging device to rise to avoid the object.

6. The coal mine tunnel safety monitoring system based on laser ranging according to claim 5 is characterized in that: It also includes a Z-axis rotation drive device for driving the laser ranging device to rotate around the Z-axis. The Z-axis rotation drive device includes a Z-axis rotation motor arranged on the lifting frame, and the main shaft of the Z-axis rotation motor is connected to the bracket.

7. The coal mine tunnel safety monitoring system based on laser ranging according to claim 6 is characterized in that: It also includes an X-axis translation device for driving the fixed frame to move along the X-axis direction, the X-axis translation device includes a mobile frame arranged on the top of the fixed frame, a mobile guide rail arranged on the top surface of the tunnel, and an X-axis translation mechanism for driving the mobile frame to move on the mobile guide rail, wherein a translation rack is arranged at the bottom of the mobile guide rail, and the translation rack extends along the length direction of the mobile guide rail; the mobile frame is installed on the mobile guide rail through a sliding structure, and the mobile frame is provided with a translation gear at a position corresponding to the translation rack, and the translation gear is meshed with the translation rack; the X-axis translation mechanism is used to drive the translation gear to rotate.

8. The coal mine tunnel safety monitoring system based on laser ranging according to claim 7 is characterized in that: There are two groups of translation racks, which are arranged in parallel. Correspondingly, there are two groups of translation gears, which are arranged in parallel. Each group of translation gears includes two translation gears, which are connected by a rotating shaft and meshed with the two groups of translation racks respectively.

9. The coal mine tunnel safety monitoring system based on laser ranging according to claim 7 is characterized in that: The sliding structure includes a guide wheel group arranged on the mobile frame and located on both sides of the mobile guide rail. The mobile guide rail is provided with a guide groove that cooperates with the guide wheel group, and the guide groove extends along the length direction of the mobile guide rail; each guide group includes guide wheels that are arranged in parallel and are rotatably connected to the mobile frame.

10. The method of the coal mine tunnel safety monitoring system based on laser ranging according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step S1: start the laser distance measuring device; Step S2: the X-axis rotation drive device drives the laser distance measuring device to rotate around the X-axis, and at the same time records the distance data between each distance measuring point on the inner wall of the lane detected by the laser distance measuring device and the laser distance measuring device; Step S3: the Y-axis rotation drive device drives the X-axis rotation drive device and the laser distance measuring device to rotate around the Y-axis by a predetermined angle; then step S2 is repeated; until the distance data between all the distance measuring points on the inner wall of the lane and the laser distance measuring device are detected; Step S4: Enter the next monitoring cycle, repeat steps S2 and S3, and complete the distance data between each distance measuring point on the inner wall of the lane and the laser distance measuring device in the next monitoring cycle; Step S5: Repeat step S4 to obtain the distance data between each distance measuring point on the inner wall of the tunnel and the laser distance measuring device in multiple monitoring cycles, and determine the safety status of the tunnel by measuring the change in the distance between the same distance measuring point and the laser distance measuring device in two or more adjacent monitoring cycles and judging whether the change value is within the allowable range; Step S6: When the tunnel is in a safe state, the coal mine tunnel safety monitoring system continues to monitor; When in an unsafe state, the alarm system in the coal mine tunnel safety monitoring system will issue an alarm prompt.

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